Air compressor



H. IVI. CAKE.

'AIR COMPRESSOR.

APPLICATLON FILED JULY s. ism.

1,316; 39. Patentedsept. 16,1919.

2 SHEETS-SHEET I.

w, fum?? HA M. CAKE.

Am coMPEssoR. APPLICATION FILED JULY 6| |918 1 ',3'1 6, 1 39 Patented Sept. 16, 1919. I 2 SHEETS-SHEE T 2- lil HOB ACE M. AKE, F PHILADELPHIA, PENNSYLVANIA.

retenes. i

Ainfcomrnsson,

Specification of Letters Patent. Patented Sept, 16, 1919,

y Application iled Jul'y 6, 1918. Serial No. 243,524.

sor for air, or the like.

vat

The principal object of the invention is to provide a multistage compressor whe-rein the same amount of energy is utilized at each compression stage.

still further object of the present invention is a multi-stage air compressor wherein the compressing elements are mounted for reciprocal action in such manner that the energy utilized in the compression action is tion comprises a compressor for air or the v like wherein the air progresses in stages through the compressor and l1s gradually as the pressure is increased reduced 1n volume and with compression elementsmounted at i chine.

intervals in the device with thediameters of the compression elements in proportion to the pressure of the air so that pressure times` .the area of a compression element 1s a con reference to the accompanying drawings wherein is illustrated preferred forms of the present invention though it will be apparentv l i that the Ainvention may be practised 1n forms other than the specific disclosure herewith, so that lit will be understood the specificA disclosure is'to be considered as illustrative and `not to be taken in the limiting sense.

art be pointed-out Throughout the drawings like characters are used to represent like parts in the several figures thereof. v Q

Figure I illustrates one form of the inventionwith certain 4parts shown in cross-sec-y tion. Fig. II illustrates a slightly different construction wherein certain of the parts are also shown incross-section.

Fig. III is a diagrammatic view illustratin the operation of the machine.`

eretofore in the art of air compressors, and the like, two systems have been in use, one comprising a multi-stage compressor wherein the compressing elements were Xedly or rigidly mounted to be positively drivenl with a definite speed ratio between the several compressing elements so that a rigid fixed relation was vat all times maintained between the several compressing blements. The other type comprises a system wherein individual independent compressors carry the compression from one stage to the. other. In thissystem no definite relation whatever is maintained between; the several compressors; and itis the general practice in this type of system to utilize pressure or stora e chambers for each stage of the compresslon operation so that at each stage the dynamic forces become a static pressure.

Since conditions ofthe atmosphere, due to the varying barometric pressure, humidity, etc., are different for different times, it is obvious that a compressor of the first-type, wherein the compressionelements are rigidly connected can not at all times, and under all conditions, be working most eiliciently for every stage of compression, so that the total eiiciency4 ofthis type of compressor is low. In the second type the efficiency is higher but it depends largely on regulation of the operation of the various compressors and this system introduces a loss. at each stage where the air changes from dynamic to static pressure..

The present invention overcomes the difficulties of the prior art by providing a multistage compressor wherein each compression element sreciprocally driven relatively to every otherA pressure element in the compressor so that at all timeseach compressor must absorb thesame amount, or proportion, of

the total horse power driving the compres-V sor. necessary to provide static chambers between the compressing elements and therefore the forces delivered to the air do not change from dynamic to static until the last and final stage of compression is passed. In view of the reciprocal relationship of the compressing elements it will be seen that each l compressor is operating at the same efficiency as every other compressor in the machine.

Referring now to the drawings and more especially to Fig. I1 the driving shaft 1 carrying the drive wheel 2 -is mountedin suitable bearings 3 and 4 which are carried by a casing 5 that is illustrated in this ligure as being conical, and of such proportions and dimensions as will be referred to later. This driving shaft 1 carries a header 6 upon which are mounted the main compensating gears 7 These compensating gears 7 mesh with beveled gears 8 and 9, one of which is carried on the tubular shaft 10 and the other of which is carried on the tubular shaft'll so that the gears i', 8, and 9 comprise the main dierential gearing A. These tubular shafts 10 and l1 are mounted to rotate on the main shaft 1. The tubular shaft 10 carries a sub-header l2 and the tubular shaft 11 carries a sub-header 13. The subheader l2 has mounted thereon sub-compensating gears l5 and the sub-header 18 carries sub-compensatingv gears 16. The sub-compensatinggears 15 mesh on one side with a bevel gear 17 on thetubular shaft 18 and these gears l5 mesh on the other side with a bevel gear 19 on the tubular shaft 20, all

to freely rotate on the shaft 11 while thefA tubular shaft 25 is mountedto freely rotate on the drivings'haft l. The shaft 20 carries the first stage compressor fan 26; the shaft 18 carries the secondl stage compressor fan 27; the shaft 22 carries the third stage'comressorvfan 28 and the shaft 25 carries the ourth stage compressor fan 29. It is to be noted that the compressor fans diminish in l size and therefore, inl-area, from the first to the last stage. The casing 5 `follows the diminishment `of diameterof the fans so that this casing is conical, as shown in Fig. I. The-,diameters of the compressor fans are preferably so proportioned that under normal' conditions where air is to be compressed from standard barometric pressure to a predetermined static pressure, the same Under these circumstances it is not.

rotation for each fan will deliver the same energy throughout the system. Since barometric pressure varies 1t is obviously impossible to maintain ideal conditions at .all times with a rigid structure wherein the fans are properly proportioned for a definite starting pressure. In the present construction, however, the differential gearings compensate for variations from definite predetermined initial pressures so that the horse power delivered at each stage of the compressor is most effectively delivered under ideal conditions.

Referring to Fig. II the structure of a driving element is substantially the same as that disclosed in Fig. I. The casing, however, is somewhat different in that each stage of the compressor is inclosed in a cylindrical part comprising a section of a whole casing so that for this type of compressor the casing is made up of cylindrical sections 30.

In order to eliminate air loss from the ends of the fan blades the blades are inclosed'in bands or hoops 31 and filler blocks 32 are provided on the interior of the casings adjacent the bands 31 so that there is no tendency of the air (which has assumed the condition of being under static pressure) to escape between the bands 3l and the side Wall of the Casings 3G.

I: operation of this air compressor the power is transmitted through the drive wheel 2 to the main shaft 1 and one-half the power is transmittedfrom the main comthe tubular shaft l() while the other half of I the power is transmitted through these compensating gears or diderential to the tubular shaft 11. 'Ihe energy in the tubular shaft 10 is likewise divided by the secondary differential gearing B sothat one-half of this energy, or one-fourth of the total energy is transmitted to the compressor fan '26 and the other one-fourth of the total energy is transmitted to the compressor fan 27. .In like manner the energy in the tubular shaft l1 isV divided by the dierential gearing C' between the compressor fans 28 and 29. By

this construction it is to be noted that each compressor fan at all times receives one'- folirth of the total driving energy and if for any reason there is a tendency of one compressor fan to receive more energy than another, the differential gearings A, B, and C immediately distribute this excess energy -among the other fans so that at substantially all times each fan absorbs the same amount of energy. The number of fans may be increased or decreased as the conditions under which the machine is to operate may require, so long as the compensating relation between the several fans is maintained.`

I claim- Y 1. An air compressor or the like comprising 1n combination a driving shaft, compensating gears carried by said driving shaft, multiple compressor members mounted for rotation about the said driving shaft, compensating means operatively connecting all of said compressor members vvith the said compensating gears to drive all of said compressor members in the same rotative direction, and a casing inclosing said compressor members. i y

2. ln an air compressor or the like the combination of a driving shaft, compensating gearing operatively connected With said drivingv shaft, a plurality of compressor members mounted for rotation about said driving shaft, and 'means operatively con-.

l necting said compressor members with said tion of each fan is dependent upon the re amount of the dii compensating means, and a casing inclosing said compressor members.

3. ln an air compressoror the like the combination of a driving shaft, a plurality of `compressor fans mounted for rotation about said shaft, a casing surrounding said compressor fans, and compensating means connectin said compressor fans with said driving saft in such manner that the rotasistance odered by the other fans.

t. lln an air compressor or the like, the combination of a driving shaft, multiple compressor fans mounted upon said driving sha a casing surrounding said fans, and compensating means operatively connecting said driving shaftvvith each of said fans f to drive all of the said fans in the same rotative direction and in such manner that each fan is adapted to deliver an equal driving shaft,

5. ln an air compressor or the like the combination of a driving shaft, multiple compressor fans mounted for rotation around said driving shaft, a casing surrounding said fans, and compensating means operatively connecting said fans with said driving shaft to drive all of the said fans 4in the same rotative direction and in such manner as to equalize the effective forces delivered by each fan.

6. ln an air compressor or the like the combination of a driving shaft, compression mechanism carried by said drivlng shaft, saldcompression mechanism comprlsing compression fans rotatable upon said shaft,

power received from said` like, the combination `of a driving shaft, a'

plurality of compressor fans mounted to ro tate on said driving shaft, differential gearing carried by said driving shaft and cooperating With said fans to transmit energy from said shaft to said fans, and. a casing surrounding said fans.

.9. fn an air compressor or the like the combination of a driving shaft, a plurality of. fans rotatably mounted on said driving shaft, a di'erential gearing mounted on said driving shaft, gear mechanism connected With each'of said fans and cooperating with said did'erential mechanism to drive said fans in the ysame rotativedirection as the riving shaft, and a'casing surrounding said ans.

l0. An air compressor or the like com-` prising in combination a driving shaft, a plurality of compressor fans. mounted for rotation about said drivngr shaft, said com# pressor fans decreasing in diameter from the inlet end of said 'compressor to the outlet end thereof, voperative means l connecting said compressor fans With said compensating mechanism to drive 4all of said comand a casing surrounding saidfans.

l1. ln an air compressor or the like'V the v combination of a driving shaft, a diderential gearing carried by said vdriving'shaft,

`tubular shafts rotatably mounted on said driving shaft and being connected to said differential gearing, secondary did'erential' gearings connected with said tubular shafts',

and compressor fans operatively connected with said secondary did'erentialgears.

l2. ln an air compressoror the like the i combination of a driving shaft, a plurality of compressor fans mounted to rotate aroundV said driving shaft, a casing surrounding saidI compressor fans,`the inlet end of said casing being larger than the outlet end thereof, and the diameter of the said cornpressor fans being proportionate to the air pressure adapted to be maintained Within the casing adjacent the fans when the devicey isv in operation, and compensating means opeatively.connectingall of said fans with said driving shaft.. i

13. An air compressor comprising in combination a driving shaft, a plurality of air compressing means mounted to rotate around said driving shaft, a plurality of differential gears operatively connecting each of said fans with `said 'drivingshafa and 'a casing surrounding said compressor members.'

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14. In. an air compressor or thelike the combination of a plurality of-dynamic comi within said casing, a driving shaft extend-y each compressor is equal to the driving force transmitted to any other compressor in the machine.

. 15. In an air compressor or. the like the.

pensators betweeny said vair compressing means and said driving means whereby the force from said driving means is at all times equally distributed among all of said air lcompressing means.

16. vIn an air compressor or the like the combination vof Aa casing providing an air passage way, a plurality ofvfans mounted ing lengthwise of said casing, and compensating means whereby all of said fans absorb the same amount of horse power vfrom the driving shaft.

17. In an air compressor or the like the combination of a casing having a large inlet end and a smaller outlet end, a plurality of air compressing means mounted within said casing, and driving devices for said means operatively connected thereto in such manner that each of 4said means at all times ab sorbs the same amount of driving energy whereby the driving force is equally d1stributed throughout all of said means.

HRACE M. CAKE. 

